1. Field of the Invention
This invention relates to improvements in and concerning a plurality of filtering plates for use in a filter which includes a plurality of filtering plates stacked up one on top of another at prescribed fixed intervals for filtering fouled water and scrapers disposed in the gaps intervening between the filtering plates for intimate sliding contact with the opposed surfaces of the adjacent filtering plates, whereby fouling particles adhering to the intervening gaps between the filtering plates will be removed by rotating either the filtering plates or the scrapers.
2. Description of the Prior Art
Conventional filtering plates have had flat upper and lower surfaces and, in order for them to permit intervention of filtering spaces therebetween, they have necessitated interposition of spacers therebetween. (Refer for example to Japanese Utility Model Registrations No. 961,449 and No. 961,450). With the filtering plates of such a construction, however, when the filter incorporating these filtering plates is rotated and the intervening scrapers consequently rub against the spacers, the spacers are made to slip in the rotating direction of the filtering plates owing to the pressure exerted by the scrapers. Consequently, shearing force is exerted to bear upon the clamping bolts inserted through the spacers, with the result that shearing force develops within the clamping bolts, possibly to the extent of deforming the bolts. This phenomenon has constituted a serious disadvantage of conventional filtering plates.